create file if non-existant

Hello, What's the best method to have cfengine create a file (and do a few edit_line's on it) without modifying it if it exists? For example, I would like cfengine to seed a file but not modify it again afterwards. I suppose I'm looking for some kind of conditional that might help. Thanks, __

Re: CF3 File Change Synchronisation Problems: " MD5 mismatch: (reply - CFD_TRUE) New file ... seems to have been corrupted in transit, aborting"

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